A Systemic Service Design Visualization Protocol for Complex Problems in Low-Risk Public Service Application and Consultation Processes

Complex public service problems with wicked-like features--including multiple actors, fragmented information, unclear responsibility boundaries, and no single uncontested solution--are difficult to structure in routine administrative settings1,21. This article presents a systematic service design visualization protocol for low-risk public service application and consultation processes, defined here as administrative services that do not determine medical treatment, legal status, financial eligibility, child protection, disciplinary outcomes, or other high-stakes rights-affecting decisions. The primary goal of this protocol is to transition from fragmented multi-actor complaints to actionable, co-designed service concepts and early-stage usability testing. The method integrates four key stages: (1) stakeholder mapping to identify actor roles and dependencies; (2) public service journey mapping to locate service breakdowns across specific touchpoints; (3) a Double Diamond co-design workshop to convert mapped pain points into targeted design challenge statements; and (4) low-fidelity prototype testing to evaluate new service materials using simulated tasks. In a representative low-risk administrative application pathway, simulated task testing with 28 participants (112 baseline and 112 post-prototype task records) showed shorter task completion time (178.4 +/- 49.6 s to 121.7 +/- 38.2 s), fewer errors (1.86 +/- 0.91 to 0.79 +/- 0.63 errors per task), and higher task success (62.5% to 82.1%) after exposure to protocol-generated materials. These results should be interpreted as task-based usability evidence because the fixed pre/post sequence may include learning effects. Ultimately, this reproducible method equips researchers, service designers, public-sector innovation teams, and trained facilitators with a structured, visually driven approach to diagnose and prototype solutions for complex public service environments.